The city of Pittsburgh will soon have a new mayor in Bill Peduto. A recent article in the Post-Gazette described his proposal to build canals at former LTV Coke Oven Plant in Hazelwood. Pittsburgh does not have an outstanding reputation when it comes to stormwater management so this could be a much-needed banner project for our city. Peduto proposes creating engineered canals at the 178-acre industrial site along the Monongahela River to encourage future development while providing a stormwater management solution to reduce the existing sewage overflow into the three rivers.
The exisitng overflow issue is primarily due to the city's combined sewer and stormwater infrastructure. In dry weather conditions, the domestic sewage and industrial wastewater that enters the system is carried by a network of underground pipes to a treatment facility called Alcosan. During periods of heavy rainfall or snowmelt, the same pipes that carry the domestic sewage and industrial wastewater also carry all of the stormwater runoff from our roadways and roofs. This volume often exceeds the capacity that the city's system can handle, so the excess is then discharged through the overflows and into the rivers. This sewage excess is a public health risk as it has been found to contain ecoli, toxins, and debris.
While Peduto's canal idea for Hazelwood is promising, it also faces a few interesting obstacles. The proposed location is a brownfield site which are very costly to remediate. However, the city of Pittsburgh has a significant amount of experience and success dealing with this issue. The Waterfront, Summerset at Frick Park, and Pittsburgh Technology Center are all examples of successful brownfield redevelopment.
Another challenge would be to connect the proposed canal to the Monongahela River. The elevation of the river to the ground elevation of the site is a difference of over 20 feet in height. This would cause the canal construction to be very deep and require large, unattractive sidewalls. But there are alternatives that would still allow successful stormwater management at the site. Incorporating a system of wet retention ponds in lieu of canals could be done. These wet retention ponds could also be designed to snake around the site giving the feeling and impression of traditional canals. The downside of this option is that boating or kayaking between these ponds and the Monongahela River would not be possible, but could still provide opportunity for walking paths, bridges and fountains. For more information on the site's development plans, we encourage you to visit the Almono Partners website.